C. Permafrost
Permafrost is the layer beneath the "active layer". The active layer consists of soil that freezes and thaws every year. However, the requirement for permafrost is that it be frozen for two or more years consecutively. This is why permafrost exists in cold environments such as tundras.
Answer:
these differentiate as a result of signaling mechanisms. ... The daughter cells divides and after each division it becomes more specialized. When it reaches a mature cell type downstream (for example, becomes a red blood cell) it will no longer divide.
The earth is divided into four main layers: the solid crust on the outside, the mantel, the outer core and the inner core. out of them, the crust is the thinnest layer of the earth, amounting for less than 1% of our planet's volume. hope this helps!
They both reproductive Pacific cells
